Theoretical study of the intrinsic magnetic properties of disordered $Fe_{1-x}Ru_x$ alloys: a mean-field approach

C. Paduani; N. S. Branco

doi:10.1088/0953-8984/20/21/215201

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arXiv · 0803.3439

Theoretical study of the intrinsic magnetic properties of disordered $Fe_{1-x}Ru_x$ alloys: a mean-field approach

C. Paduani·N. S. Branco

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Abstract

The magnetic properties of the $Fe_{1-x}Ru_x$ alloy system for 0 $\leq$ x $\leq$ 0.10 are studied by using a mean-field approximation based on the Bogoliubov inequality. Ferromagnetic Fe-Fe spin correlations and antiferromagnetic Fe-Ru and Ru-Ru exchanges have been considered to describe the temperature dependence of the Curie temperature and low temperature magnetization. A composition dependence has been imposed in the exchange couplings, as indicated by experiments. From a least-square fitting procedure to the experimental results an estimation of the interaction parameters was obtained, which yielded the low temperature dependence of the magnetization and of the ferromagnetic Curie temperature. A good agreement was obtained with available experimental results.

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C. Paduani, N. S. Branco. 2008-03-24. Theoretical study of the intrinsic magnetic properties of disordered $Fe_{1-x}Ru_x$ alloys: a mean-field approach. https://doi.org/10.1088/0953-8984%2F20%2F21%2F215201

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